feat(mhu): add MHUv3 wrapper APIs for RSS comm driver
RSS comm driver interfaces with MHUv3 driver through specific
API calls. Add APIs to support the interface.
Signed-off-by: Aziz IDOMAR <aziz.idomar@arm.com>
Signed-off-by: Sayanta Pattanayak <sayanta.pattanayak@arm.com>
Signed-off-by: Shriram K <shriram.k@arm.com>
Signed-off-by: Vijayenthiran Subramaniam <vijayenthiran.subramaniam@arm.com>
Signed-off-by: Joel Goddard <joel.goddard@arm.com>
Change-Id: I815d43ca548d3640fceb4c91fe3bbeec31687210
diff --git a/drivers/arm/mhu/mhu_wrapper_v3_x.c b/drivers/arm/mhu/mhu_wrapper_v3_x.c
new file mode 100644
index 0000000..b3d51e3
--- /dev/null
+++ b/drivers/arm/mhu/mhu_wrapper_v3_x.c
@@ -0,0 +1,462 @@
+/*
+ * Copyright (c) 2024, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+#include <drivers/arm/mhu.h>
+
+#include "mhu_v3_x.h"
+
+#define MHU_NOTIFY_VALUE U(1234)
+
+#ifndef ALIGN_UP
+#define ALIGN_UP(num, align) (((num) + ((align) - 1)) & ~((align) - 1))
+#endif
+
+/*
+ * MHUv3 Wrapper utility macros
+ */
+#define IS_ALIGNED(val, align) (val == ALIGN_UP(val, align))
+
+/*
+ * MHU devices for host:
+ * HSE: Host to Secure Enclave (sender device)
+ * SEH: Secure Enclave to Host (receiver device)
+ */
+struct mhu_v3_x_dev_t mhu_hse_dev = {0, MHU_V3_X_PBX_FRAME};
+struct mhu_v3_x_dev_t mhu_seh_dev = {0, MHU_V3_X_MBX_FRAME};
+
+/* MHUv3 driver error to MHUv3 wrapper error mapping */
+static enum mhu_error_t error_mapping_to_mhu_error_t(enum mhu_v3_x_error_t err)
+{
+ switch (err) {
+ case MHU_V_3_X_ERR_NONE:
+ return MHU_ERR_NONE;
+
+ case MHU_V_3_X_ERR_NOT_INIT:
+ return MHU_ERR_NOT_INIT;
+
+ case MHU_V_3_X_ERR_UNSUPPORTED_VERSION:
+ return MHU_ERR_UNSUPPORTED_VERSION;
+
+ case MHU_V_3_X_ERR_UNSUPPORTED:
+ return MHU_ERR_UNSUPPORTED;
+
+ case MHU_V_3_X_ERR_INVALID_PARAM:
+ return MHU_ERR_INVALID_ARG;
+
+ default:
+ return MHU_ERR_GENERAL;
+ }
+}
+
+static enum mhu_error_t signal_and_wait_for_clear(
+ void *mhu_sender_dev, uint32_t value)
+{
+ enum mhu_v3_x_error_t err;
+ struct mhu_v3_x_dev_t *dev;
+ uint8_t num_channels;
+ uint32_t read_val;
+
+ dev = (struct mhu_v3_x_dev_t *)mhu_sender_dev;
+
+ if ((dev == NULL) || (dev->base == 0)) {
+ return MHU_ERR_INVALID_ARG;
+ }
+
+ err = mhu_v3_x_get_num_channel_implemented(dev,
+ MHU_V3_X_CHANNEL_TYPE_DBCH, &num_channels);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+
+ /* Wait for any pending acknowledgment from transmitter side */
+ do {
+ err = mhu_v3_x_doorbell_read(dev, num_channels - 1, &read_val);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+ } while ((read_val & value) == value);
+
+ /* Use the last channel to notify that a transfer is ready */
+ err = mhu_v3_x_doorbell_write(dev, num_channels - 1, value);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+
+ /* Wait until receiver side acknowledges the transfer */
+ do {
+ err = mhu_v3_x_doorbell_read(dev, num_channels - 1, &read_val);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+ } while ((read_val & value) == value);
+
+ return error_mapping_to_mhu_error_t(MHU_V_3_X_ERR_NONE);
+}
+
+static enum mhu_error_t wait_for_signal(
+ void *mhu_receiver_dev, uint32_t value)
+{
+ enum mhu_v3_x_error_t err;
+ struct mhu_v3_x_dev_t *dev;
+ uint32_t read_val;
+ uint8_t num_channels;
+
+ dev = (struct mhu_v3_x_dev_t *)mhu_receiver_dev;
+
+ if ((dev == NULL) || (dev->base == 0)) {
+ return MHU_ERR_INVALID_ARG;
+ }
+
+ err = mhu_v3_x_get_num_channel_implemented(dev,
+ MHU_V3_X_CHANNEL_TYPE_DBCH, &num_channels);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+
+ do {
+ err = mhu_v3_x_doorbell_read(dev, num_channels - 1, &read_val);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+ } while (read_val != value);
+
+ return error_mapping_to_mhu_error_t(err);
+}
+
+static enum mhu_error_t clear_and_wait_for_signal(
+ void *mhu_receiver_dev, uint32_t value)
+{
+ enum mhu_v3_x_error_t err;
+ struct mhu_v3_x_dev_t *dev;
+ uint8_t num_channels;
+
+ dev = (struct mhu_v3_x_dev_t *)mhu_receiver_dev;
+
+ if ((dev == NULL) || (dev->base == 0)) {
+ return MHU_ERR_INVALID_ARG;
+ }
+
+ err = mhu_v3_x_get_num_channel_implemented(dev,
+ MHU_V3_X_CHANNEL_TYPE_DBCH, &num_channels);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+
+ /* Clear all channels */
+ for (int i = 0; i < num_channels; i++) {
+ err = mhu_v3_x_doorbell_clear(dev, i, UINT32_MAX);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+ }
+
+ return wait_for_signal(mhu_receiver_dev, value);
+}
+
+static enum mhu_error_t validate_buffer_params(uintptr_t buf_addr)
+{
+ if ((buf_addr == 0) || (!IS_ALIGNED(buf_addr, sizeof(uint32_t)))) {
+ return MHU_ERR_INVALID_ARG;
+ }
+
+ return MHU_ERR_NONE;
+}
+
+enum mhu_error_t mhu_init_sender(uintptr_t mhu_sender_base)
+{
+ enum mhu_v3_x_error_t err;
+ struct mhu_v3_x_dev_t *dev;
+ uint8_t num_ch;
+ uint32_t ch;
+
+ assert(mhu_sender_base != (uintptr_t)NULL);
+
+ mhu_hse_dev.base = mhu_sender_base;
+ dev = (struct mhu_v3_x_dev_t *)&mhu_hse_dev;
+
+ /* Initialize MHUv3 */
+ err = mhu_v3_x_driver_init(dev);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+
+ /* Read the number of doorbell channels implemented in the MHU */
+ err = mhu_v3_x_get_num_channel_implemented(
+ dev, MHU_V3_X_CHANNEL_TYPE_DBCH, &num_ch);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ } else if (num_ch < 2) {
+ /* This wrapper requires at least two channels implemented */
+ return MHU_ERR_UNSUPPORTED;
+ }
+
+ /*
+ * The sender polls the postbox doorbell channel window status register
+ * to get notified about successful transfer. So, disable the doorbell
+ * channel's contribution to postbox combined interrupt.
+ *
+ * Also, clear and disable the postbox doorbell channel transfer
+ * acknowledge interrupt.
+ */
+ for (ch = 0; ch < num_ch; ch++) {
+ err = mhu_v3_x_channel_interrupt_disable(
+ dev, ch, MHU_V3_X_CHANNEL_TYPE_DBCH);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+ }
+
+ return MHU_ERR_NONE;
+}
+
+enum mhu_error_t mhu_init_receiver(uintptr_t mhu_receiver_base)
+{
+ enum mhu_v3_x_error_t err;
+ struct mhu_v3_x_dev_t *dev;
+ uint32_t ch;
+ uint8_t num_ch;
+
+ assert(mhu_receiver_base != (uintptr_t)NULL);
+
+ mhu_seh_dev.base = mhu_receiver_base;
+ dev = (struct mhu_v3_x_dev_t *)&mhu_seh_dev;
+
+ /* Initialize MHUv3 */
+ err = mhu_v3_x_driver_init(dev);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+
+ /* Read the number of doorbell channels implemented in the MHU */
+ err = mhu_v3_x_get_num_channel_implemented(
+ dev, MHU_V3_X_CHANNEL_TYPE_DBCH, &num_ch);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ } else if (num_ch < 2) {
+ /* This wrapper requires at least two channels implemented */
+ return MHU_ERR_UNSUPPORTED;
+ }
+
+ /* Mask all channels except the notifying channel */
+ for (ch = 0; ch < (num_ch - 1); ch++) {
+ /* Mask interrupts on channels used for data */
+ err = mhu_v3_x_doorbell_mask_set(dev, ch, UINT32_MAX);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+ }
+
+ /* Unmask doorbell notification channel interrupt */
+ err = mhu_v3_x_doorbell_mask_clear(dev, (num_ch - 1), UINT32_MAX);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+
+ /*
+ * Enable the doorbell channel's contribution to mailbox combined
+ * interrupt.
+ */
+ err = mhu_v3_x_channel_interrupt_enable(dev, (num_ch - 1),
+ MHU_V3_X_CHANNEL_TYPE_DBCH);
+ if (err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(err);
+ }
+
+ return MHU_ERR_NONE;
+}
+
+/*
+ * Public function. See mhu.h
+ *
+ * The basic steps of transferring a message:
+ * 1. Send the size of the payload on Channel 0. It is the very first Bytes of
+ * the transfer. Continue with Channel 1.
+ * 2. Send the payload, writing the channels one after the other (4 Bytes
+ * each). The last available channel is reserved for controlling the
+ * transfer. When the last channel is reached or no more data is left, STOP.
+ * 3. Notify the receiver using the last channel and wait for acknowledge. If
+ * there is still data to transfer, jump to step 2. Otherwise, proceed.
+ *
+ */
+enum mhu_error_t mhu_send_data(const uint8_t *send_buffer, size_t size)
+{
+ enum mhu_error_t mhu_err;
+ enum mhu_v3_x_error_t mhu_v3_err;
+ uint8_t num_channels;
+ uint8_t chan;
+ uint32_t *buffer;
+ struct mhu_v3_x_dev_t *dev;
+
+ if (size == 0) {
+ return MHU_ERR_NONE;
+ }
+
+ dev = (struct mhu_v3_x_dev_t *)&mhu_hse_dev;
+ chan = 0;
+
+ if ((dev == NULL) || (dev->base == 0)) {
+ return MHU_ERR_INVALID_ARG;
+ }
+
+ mhu_err = validate_buffer_params((uintptr_t)send_buffer);
+ if (mhu_err != MHU_ERR_NONE) {
+ return mhu_err;
+ }
+
+ mhu_v3_err = mhu_v3_x_get_num_channel_implemented(dev,
+ MHU_V3_X_CHANNEL_TYPE_DBCH, &num_channels);
+ if (mhu_v3_err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(mhu_v3_err);
+ }
+
+ /* First send the size of the actual message. */
+ mhu_v3_err = mhu_v3_x_doorbell_write(dev, chan, (uint32_t)size);
+ if (mhu_v3_err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(mhu_v3_err);
+ }
+ chan++;
+
+ buffer = (uint32_t *)send_buffer;
+ for (size_t i = 0; i < size; i += 4) {
+ mhu_v3_err = mhu_v3_x_doorbell_write(dev, chan, *buffer++);
+ if (mhu_v3_err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(mhu_v3_err);
+ }
+
+ if (++chan == (num_channels - 1)) {
+ /* Use the last channel to notify transfer complete */
+ mhu_err = signal_and_wait_for_clear(
+ dev, MHU_NOTIFY_VALUE);
+ if (mhu_err != MHU_ERR_NONE) {
+ return mhu_err;
+ }
+ chan = 0;
+ }
+ }
+
+ if (chan != 0) {
+ /* Use the last channel to notify transfer complete */
+ mhu_err = signal_and_wait_for_clear(dev, MHU_NOTIFY_VALUE);
+ if (mhu_err != MHU_ERR_NONE) {
+ return mhu_err;
+ }
+ }
+
+ return MHU_ERR_NONE;
+}
+
+/*
+ * Public function. See mhu.h
+ *
+ * The basic steps of receiving a message:
+ * 1. Read the size of the payload from Channel 0. It is the very first
+ * 4 Bytes of the transfer. Continue with Channel 1.
+ * 2. Receive the payload, read the channels one after the other
+ * (4 Bytes each). The last available channel is reserved for controlling
+ * the transfer.
+ * When the last channel is reached clear all the channels
+ * (also sending an acknowledge on the last channel).
+ * 3. If there is still data to receive wait for a notification on the last
+ * channel and jump to step 2 as soon as it arrived. Otherwise, proceed.
+ *
+ */
+enum mhu_error_t mhu_receive_data(uint8_t *receive_buffer, size_t *size)
+{
+ enum mhu_error_t mhu_err;
+ enum mhu_v3_x_error_t mhu_v3_err;
+ uint32_t msg_len;
+ uint8_t num_channels;
+ uint8_t chan;
+ uint32_t *buffer;
+ struct mhu_v3_x_dev_t *dev;
+
+ dev = (struct mhu_v3_x_dev_t *)&mhu_seh_dev;
+ chan = 0;
+
+ mhu_err = validate_buffer_params((uintptr_t)receive_buffer);
+ if (mhu_err != MHU_ERR_NONE) {
+ return mhu_err;
+ }
+
+ mhu_v3_err = mhu_v3_x_get_num_channel_implemented(dev,
+ MHU_V3_X_CHANNEL_TYPE_DBCH, &num_channels);
+ if (mhu_v3_err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(mhu_v3_err);
+ }
+
+ /* Busy wait for incoming reply */
+ mhu_err = wait_for_signal(dev, MHU_NOTIFY_VALUE);
+ if (mhu_err != MHU_ERR_NONE) {
+ return mhu_err;
+ }
+
+ /* The first word is the length of the actual message. */
+ mhu_v3_err = mhu_v3_x_doorbell_read(dev, chan, &msg_len);
+ if (mhu_v3_err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(mhu_v3_err);
+ }
+ chan++;
+
+ if (*size < msg_len) {
+ /* Message buffer too small */
+ *size = msg_len;
+ return MHU_ERR_BUFFER_TOO_SMALL;
+ }
+
+ buffer = (uint32_t *)receive_buffer;
+ for (size_t i = 0; i < msg_len; i += 4) {
+ mhu_v3_err = mhu_v3_x_doorbell_read(dev, chan, buffer++);
+ if (mhu_v3_err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(mhu_v3_err);
+ }
+
+ /* Only wait for next transfer if still missing data. */
+ if (++chan == (num_channels - 1) && (msg_len - i) > 4) {
+ /* Busy wait for next transfer */
+ mhu_err = clear_and_wait_for_signal(
+ dev, MHU_NOTIFY_VALUE);
+ if (mhu_err != MHU_ERR_NONE) {
+ return mhu_err;
+ }
+ chan = 0;
+ }
+ }
+
+ /* Clear all channels */
+ for (uint8_t i = U(0); i < num_channels; i++) {
+ mhu_v3_err = mhu_v3_x_doorbell_clear(dev, i, UINT32_MAX);
+ if (mhu_v3_err != MHU_V_3_X_ERR_NONE) {
+ return error_mapping_to_mhu_error_t(mhu_v3_err);
+ }
+ }
+
+ *size = msg_len;
+
+ return MHU_ERR_NONE;
+}
+
+size_t mhu_get_max_message_size(void)
+{
+ enum mhu_v3_x_error_t err;
+ uint8_t num_channels;
+
+ err = mhu_v3_x_get_num_channel_implemented(&mhu_seh_dev,
+ MHU_V3_X_CHANNEL_TYPE_DBCH, &num_channels);
+
+ assert(err == MHU_V_3_X_ERR_NONE);
+ assert(num_channels != U(0));
+ /*
+ * Returns only usable size of memory. As one channel is specifically
+ * used to inform about the size of payload, discard it from available
+ * memory size.
+ */
+ return (num_channels - 1) * sizeof(uint32_t);
+}